Cat 235 excavator engine swap

Picked up a 1976 model 235 excavator the other day on an auction and the motor is bad. Need to find a good runner to swap into it. Ran across a D333c engine and was told it will work but want to verify it before we buy it and drive 4 hours to go make the swap and find out it won't work. I did not get an engine serial # off of our excavator but believe it to be a 3306 engine. Any help would be greatly appreciated.

You can do an engine swap BUT for best results stick to a 3306 Precombustion chamber engine.
That way you can reuse all of the parts from the original engine, Especially the fuel system. That way you can complete a good job and have a machine that will work properly with out destroying it's self. This whole job worries me as to you getting very deep into trouble(expense). My advise to you would be to pass up this machine and let them part it out. Keep looking for a 235 machine in working condition. They are a great machine but it's very difficult to get a brand new pump control servo that is any good these days. Might be money ahead to get a 225 with a Rexroth pump(two pumps in one body) or a newer 300 series machine. They are repairable with better results.
Later Bob

I"ve got to chime in here and agree with Bob. Having worked on a customers 235 many times, your right in the fact that it should have a 3306 engine in it. I wish I could check my manual to be sure I"m right here (I"m moving my office and have most of the manuals boxed up for awhile) but if I remember right the injection pump on the excavator engines has a sensing line from the hydraulic system that aids it in responding to the load applied by the pumps. IF I"m right here, and it has been about 8 years since my customer sold his machine, the D333 would have a hard time working properly without that sensing line connected like it should be. Ultimately, trying to do a engine swap in a machine as complex as an excavator will never be an easy task.

Now you say the engine is "bad". Bad can have many different meanings from a blown head gasket to a rod hanging out the side of the block. As long as the engine hasn"t sustained any major damage, why not just rebuild it? To me, if you"ve got enough mechanical knowledge to even think about, much less attempt an engine swap like this, rebuilding an engine as simple as a 3306 shouldn"t present any major problems for you. Once you get rid of the labor expense to have someone else do everything, I"d make a guess that the parts needed to do the rebuild would be a small expense in comparison to the cost to shoehorn in a different engine when you factor in the time trying to make everything fit as well as the cost of any fabrication, etc needed for the same reason.

That all said, if you want to do a rebuild give the guys at Offroad Equipment Parts a call. I priced out parts for an engine rebuild on an old D6 a few years back from both the dealerships, and aftermarket places. These guys sell a combination of NOS CAT parts as well as aftermarket parts and they came in right under half the cost of the dealership, and a good bit below anybody else I called too.


Regardless of what route you take good luck.
Offroad Equipment Parts

Thanks for the replies guys, an engine overhaul is definitely do-able for us, we did a C-15 Cat in our Peterbilt last fall with no issues its just that the excavator is sitting 4-1/2 hours away from us and we have limited time to get it out of there (bought at an auction in the condition its in) so we thought if we could find a decent running engine that would swap in we could pull the bad one out and replace with a good one in a day, but rebuilding it might not be totally out of the question either. If we can't run across a good runner that might just be what we have to do. I am glad to hear of the injection pump sending line, there was a small 1/8" line connected up to the injection pump that ran forward toward the hydraulics and that is probably what it is. Thanks for the help.

You can disconnect the final drive pinions and carefully push it onto and off of a float to move it. Just be careful and lock up the pinions for travel. No connection to fuel system from hyd system. Just need fuel system set up for excavator that's all.
Later Bob

There is a 3306 Cat on New Castle , Pa 's Craigs list in heavy equipment section . I should have said i saw it on the Youngstown Ohio Craigs list but the engine is in New Castle Pa.